He meant me. I was still Linda Carmichael then. My first album's release was still a month off, and the protest organiser was here to see Sumner.

Bobby smoothed his trousers down, passing his brown beret through his hands. He smelt of rain, of olive oil, and garlic. He smelt exotic, to me.

"No, gracias," he said. "Got to keep moving. But you'll come, yeah? I love your records, man. It would mean a lot to have you there."

"Count us in," Sumner said, as the guy got up to go. As I showed Bobby to the door, I wondered if he could read Sumner's body language.

"We need you guys to support us, man," he said. I told him I knew and gave him vague directions to Joni Mitchell's place. When I went back through to the living room, Sumner was staring at the damp patch on the sofa.

"I just don't know it's our kind of thing, Linda," he said, as if he knew what I was going to ask. "I mean, I'm against the war, and everything, but these guys…they're just so…"

"Mexican?" I said.

"No, it's not that. You know it's not that."

It was our first argument about politics. Sumner was pretty lazy, politically, but I harped on about how important it was to get involved that he agreed just to shut me up.

That first March we went to, some time in Spring, 1971. There was a cold clear light to the day, bouncing off the helmets and visors of the National Guardsmen. We marched under some sort of banner: I think it said something like 'Artists against the Draft.' Just me holding one end of it, Sumner at the other, and a raggle taggle of session men and hangers on in between.

The year before, not long after Julie and I arrived, there had been what turned out to be the biggest of the Chicano demonstrations, and the cops had opened fire. So we were a jittery bunch, that day, marching beside our Mexican-American brothers, Sumner in his army surplus shirt. This was in East L.A., with the housing projects stretching away up the hill ahead of us.

Then something happened. I don't know what the flashpoint was, but up ahead the tear gas canisters started going off, the Brown Berets in front of us began to tunr and scatter, and the other half of the banner went slack. I turned, and Sumner had disappeared in the wheeling, panicking mob of protesters and cops. I didn't know if he had been hit, or just cut and run.

I ran, like everyone else, of course. Didn't want a National Guardsman breaking my arm with a baton any more than the rest of them. The confusion wasn't helped by the joint I'd had before we came out: I remember shouting Sumner's name, main streets turning into side streets, crowds thinning to ones and twos, the adrenalin gradually ebbing away. Eventually there was just me and a couple of locals, who took pity on me and called their brother in law who ran a taxi firm, making me coffee in their ground floor apartment that smelt of bitter oranges.

I found out later that Sumner had experienced a different kind of hospitality with a Cuban girl called Rosa, who turned up at the house two nights later, looking for him.

That kind of killed the Chicano Moratorium for me, although it petered out by itself later that year, if I remember right. I never saw Bobby Guttierez again. Sumner said he'd heard he was a CIA plant, an agent provocateur trying to discredit the organisation. But then, Sumner said a lot of things.

It was a year or so later that picture came out, the one of the girl in a Vietnamese village after a napalm attack. I reckon that picture, going into millions of homes on the front of a newspaper, did just as much as all the rallies and marches ever did.

They say a picture's worth a thousand words. Well, in my case, it was worth three verses, chorus and a bridge.